Field of the Invention
Exemplary embodiments of the present invention relate to a vehicle broadband antenna, and more particularly, to a vehicle broadband antenna that is an antenna for LTE & V2X installed in the vicinity of a vehicle crash pad.
Description of the Related Art
With the development of information and communication, the concept of intelligent transportation systems (hereinafter, referred to as “ITSs”) was already introduced in the 1990s for the road section and the concept of ubiquitous was also introduced in the 2000s for the road section, with the consequence that the ITSs have further progressed. These ITSs are generally aimed at realizing rapid, safe, and pleasant next-generation traffic systems suitable for information societies that are increasingly accelerated.
ITS services are classified into advanced traffic management systems (ATMSs), advanced traveler information systems (ATISs), advanced public transportation systems (APTSs), commercial vehicle operations (CVOs), and advanced vehicle and highway systems (AVHSs).
The ATMSs include an automated fare collection system, an automatic enforcement system, etc., the ATISs include a driver information system, an optimal route guidance system, etc., the APTSs include a public transportation information system, a public transportation management system, etc., the CVOs include a universal pass system, a commercial vehicle management system, etc., and the AVHSs include a rear-end prevention system, a balloon tire warning system, etc.
As described above, vehicle-to-vehicle (V2V) communication and vehicle-to-infrastruction (V2I) communication are essential for the ITSs having various services, and various types of information are transmitted and received in the vehicle therethrough. The V2I communication is a communication method for providing road traffic services through roadside base stations.
Accordingly, in the V2V communication and the V2I communication for provision of ITS services, transmission and reception are performed in a 5.8 GHz frequency band, and it has been required to develop small antennas having improved reception performance for use in WAVE (Wireless Access in Vehicular Environment) environments in recent years.
In recent years, an inverted-L antenna (ILA) is mainly used for a mobile phone. The ILA has a structure that combines a vertical antenna such as a monopole with a horizontal antenna attached to the tip of the monopole. The ILA is an antenna that may be manufactured to have a low height since the frequency characteristic of the ILA is determined by the horizontal antenna rather than the vertical antenna. In addition, the ILA is an antenna that generally has a horizontal wavelength of λ/4 and a smaller band characteristic than the typical monopole antenna, and is mostly used for mobile and portable wireless devices.
The ILA, as a multiband antenna that satisfies three GSM 900 (880 to 960 MHz), DCS 1800 (1710 to 1880 MHz), and WCDMA (1920 to 2170 MHz) bands, represents satisfactory performance in the DCS 1800 and WCDMA bands. However, the ILA has a disadvantage of narrowband characteristics and may not obtain a satisfactory voltage standing wave ratio (VSWR) in the low GSM 900 band. Meanwhile, an antenna is reconstituted to be suitable when frequencies are changed due to the interference in the vicinity of the antenna according to the mounting position thereof. However, since the antenna line of the ILA is formed by injection molding, it is necessary to manufacture an additional mold to thus cause an increase in development cost, and it may take a long time to manufacture the mold.
The conventional vehicle antenna includes a glass antenna and a roof antenna. The glass antenna is a typical radio antenna that is installed on the rear window glass of the vehicle, and the roof antenna is an antenna that is installed on the roof of the vehicle to have a very large decisive directionality.
Accordingly, when a broadband antenna is intended to be added to the conventional antenna, it is difficult to add the broadband antenna thereto due to a small space of the existing rear window or roof.